Improvement in metallic packings for piston-rods



UNITED STATES PATENT OEEICE.

JAMES T. GILMCEE AND JOHN E. CARTER, or BosToN, MASSACHUSETTS.

IMPROVEMENT IN METALLIC PACKINGS FOR PISTON-RODS, &c.

Specification forming part of Letters Patent No. 149,851, dated Ap1il2l,1t574; application liled September 10, 1873.

To all whom it may concern Be it known that we, JAMES T. GILMORE and JOHN H. CARTER., of Boston, Suffolk county, Massachusetts, have invented certain Improvements in Metallic Packings for Piston-Rods, Sto., of which the following is a specification:

This improvement is based upon a class of packings for piston-rods and other objects, in which a series of segmental plates are employed, disposed within a steam-tight box e11- circling the piston-rod, and pressed closely up to it by springs, in order to produce a steamtight joint, and prevent waste of steam. A particular example of this class of valve, and one to which our improvement has especial reference, is that shown in Letters Patent of the United States numbered 132,024, and issued on the 8th day of October, 1872, to Phillip W. Richards, of Boston, Massachusetts, as inventor, in connection with other parties as assignees. Y In this Richards packing there is employed an annular plate or washer, laid flatwise upon each series of segmental plates, and

tted thereto with a ground or other perfect joint, to prevent passage of steam, springs being placed between the lower' Washer and the bottom of the box, which drive the entire series of segmental plates and rings outward, and so as to produce a steam-tight joint between the outer washer and the head or cap of the box which incloses the different parts, the abutting faces of the last-named washer and of the head ofthe box being ground or nicely fitted, in order that any steam. which may clandestinely find its way to the interior of such box shall not escape about the pistonrod, which passes through its head. In the practical use of this packing, we have found that the washers or following-rings, as therein employed, are practically useless, as steam escapes through or about them or the segments, and the wear upon them is onesided,unequal, and very objectionable; therefore, in seeking for some remedy for this evil, we have devised our present improvement, which has beenfound to answer the purposes admirably. In carrying out our improvement, we employ a box or case to contain the parts, but we discard a cap or cover, and reverse the position, of it shown in the Richards patent,

and bolt it directly to the stufiing-box cap, if applied to an old engine, or to the cylinderhead, it' a new engine. We take no especial pains to exclude steam from the interior of the box, as no harm results from its presence.

rlhe drawings accompanying this specification represent, in Figure l, a vertical section o f a rod-packing device containing our improvements, Fig. 2 being an end view of the rod and clasp embracing it, and the packingrings.

In these drawings, ,A represents a circular box or case, the outer end or head of which is pierced with a hole, B, of a diameter considerably larger than that of the piston-rod C, which passes through it, the open end of said box A being securely bolted to the outer end or cap of the stuffing-box, if the device is applied to old engines, or to the cylinder-head when applied to new engines, as in the latter instance no stuffing-box exists, this device taking its place. F F and G G represent two sets `of segmental plates, the inner concave faces of which hug closely up to the pistonL rod C, such plates being so arranged as to break joints, and being impelled toward and against the periphery of the rod by suitable springs H H, arranged within a four-armed yoke or clasp, I, as shown in the drawings, such plates serving to effectually exclude steam, and prevent the same from creeping outward about the rod which passes through the yoke. The lower or inner part of the yoke Iterminates in a concentric tapering or conical head, J, while embracing or inclosing this head is an annular plate, or flat ring, or wash,- er, K, which encircles the rod, the joint between the ring and head J being a ground one, to prevent passage of steam at this point. The abutting faces of the hea-d or teat J, and the opening of the ring K are not ila-t faces, but arel curvilinear or bowl-shaped, as represented, in order that they may rock or sway upon one another, for purposes hereinafter stated. The orice B in the head or closed end A of the box A is, as before stated, of somewhatlarger diameter than that of the pis- `tonrod, and Within the opening or seat B we dispose a second annular plate or at ring, L, which engi/goles thepiston-rod, the joint between thel ring Land the orifice B being similar to that above described as existing between the teat J and plate K-that is to say, as composed of curvilinear faces, the joint in fact being, practically, a semtball-and-socket one.

1t frequently happens, in the use oi' the valve above mentioned, that the tilting or swayingof the piston-rod out of axial alignment with the en gine-cylinder and the box A, results in unequal wear upon the rings or plates which abut against the opposite inner ends of such box, and steam is allowed to escape through the orices which receive the piston-rod, and wear, once having begun, oftentimes rapidly destroys the rings, or renders the packingbox inoperative..

Owing to the nature of the joints between the teat J and ring K, and the ring L and orifice B, the piston-rod is allowed to sway or tilt out of alignment with the axis of the cylinder or of the box A without injury, as the rings K and L follow its movements, and, owing to their semi-ball-andsocket character, always maintain the saine steam tight joint. By

this means no steam is allowed to pass from the outer end of the box A, and the wear upon the parts is very slow, and is equal in all directions.

1. The combination, with the inverted box A, and the segmental packing-plates F G, of the ring,` or washer L, constructed and operatl ing in connection with said parts, substantially as and for the purposes described.

2. The combination, with the ring L, formed and operating as described, of the conical head or teat J, and ring K, substantially as and for purposes stated.

3. The yoke or clasp I, with its arms e1nbracing the segments F G, and its conical teat J operating with the ring K, as .explained J. T. GILMORE.

' JOHN H. CARTER.

-Witnesses FRANCIS E. FAXoN, W. E. BOARDMAN, F. GUR'rrs. 

